i think singing a song should not be mandatory to anyone. first ppl should explain muslims that vande-matram doesnot have any reference to the idol worship and just shows the respect for the mother india. i dont think then it should be a problem for anyone. there were some paragraphs in song vande-matram that were refering to worshiping mother india but those were deleted and not present in today's version of vande-matram. vande-matram was the slogan used by our freedom fighters across all religions and it should not become a point of fight between hindu-muslims.
regarding the sardar patel story you have told, i dont think that this is true. this must be born out from imagination.